/*
 * Copyright 2013 serso aka se.solovyev
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 * Contact details
 *
 * Email: se.solovyev@gmail.com
 * Site:  http://se.solovyev.org
 */

package org.solovyev.android.calculator.history;

import javax.annotation.Nonnull;
import javax.annotation.Nullable;

import org.simpleframework.xml.Serializer;
import org.simpleframework.xml.core.Persister;

import java.io.StringWriter;
import java.util.List;

/**
 * User: serso
 * Date: 12/17/11
 * Time: 9:59 PM
 */
class HistoryUtils {

	// not intended for instantiation
	private HistoryUtils() {
		throw new AssertionError();
	}

	public static void fromXml(@Nullable String xml, @Nonnull List<CalculatorHistoryState> historyItems) {
		if (xml != null) {
			final Serializer serializer = new Persister();
			try {
				final History history = serializer.read(History.class, xml);
				for (CalculatorHistoryState historyItem : history.getHistoryItems()) {
					historyItems.add(historyItem);
				}
			} catch (Exception e) {
				throw new RuntimeException(e);
			}
		}
	}

	@Nonnull
	public static String toXml(@Nonnull List<CalculatorHistoryState> historyItems) {
		final History history = new History();
		for (CalculatorHistoryState historyState : historyItems) {
			if (historyState.isSaved()) {
				history.getHistoryItems().add(historyState);
			}
		}

		final StringWriter xml = new StringWriter();
		final Serializer serializer = new Persister();
		try {
			serializer.write(history, xml);
		} catch (Exception e) {
			throw new RuntimeException(e);
		}
		return xml.toString();
	}
}
